Melanoma is on the rise, particularly in people younger than age 30.

With current estimates that 1 in 5 Americans will develop skin cancer in their lifetime, dermatologists and cancer groups are stepping up efforts to screen patients at least once a year and teach them to perform their own self-exams as often as monthly.

Doctors are creating photographic "mole maps" to track changes over time, and some dermatologists are turning to a new, noninvasive device that helps determine which moles...